#!/bin/bash

no1=4;
no2=5;

#let 命令操作简单算数运算
let result=no1+no2;
echo ${result};

#自加 自减
let no1++;
let no2++;

echo "no1=${no1}";
echo "no2=${no2}";

#加减法简写
let no1+=6;
let no2-=6;

echo "no1=${no1}";
echo "no2=${no2}";